隧道电子激发的辛硫醇条纹相自组装膜上卟啉单分子荧光

Tunneling Electron Induced Fluorescence from Single Porphyrin Molecules Decoupled by Striped-Phase Octanethiol Self-assembled Monolayer

利用扫描隧道显微镜诱导发光技术，对单个卟啉分子的电致荧光现象进行了研究．为了避免金属衬底对单个卟啉分子的荧光淬灭，利用条纹状辛硫醇自组装膜作为脱耦合层，实现了单个中性卟啉分子的电致荧光，并且发现分子荧光的产生呈现双极性特征．另外，分子瓣上的荧光强度要强于分子中心的荧光强度．

We investigate tunneling electron induced luminescence from isolated single porphyrin molecules that are decoupled by striped-phase self-assembled monolayer of octanethiol from the underneath Au（111） substrate. Intrinsic single-molecule electroluminescence has been realized by such decoupling at both bias polarities. The photon emission intensity acquired from the molecular lobe is found stronger than that from the molecular center. These re- sults provide useful information on the understanding of electroluminescent behavior and mechanism in molecular tunnel junctions.